Solr Unique key Issue in DSE

Hi ,
I have been working with DSE Solr for past few days .
I am currently facing an issue specifying unique key in Solr schema.xml .

In schema, one needs to specify the unique key , which is the row_key in cassandra .
In my case row_key is been created dynamically , what is the work around for this situation?

Also I have a column named "id" in my CF which is different from row_key. What i observe is Solr is inserting row_key value in this "id" field . Is there a way to stop Solr inserting in this field , also I dont see this Column in describe CF , once its been indexed by Solr .

Please help me clear my understanding , as It will help us make decision to use DSE or not .

@srinivasrao - If my row key is a composite key then what type do I specify in schema.xml
@alexliu - Are you saying that there is no need to provide
<uniqueKey>id</uniqueKey>
in schema.xml ?
As when I tried to do so , I got exception stating I need a uniqueKey .